Atomic number:35

Group numbers:17

Period:4

Electronic configuration:[Ar] 3d¹⁰ 4s² 4p⁵

Formal oxidation number:-1 +1 +5

Electronegativities:2.96

Atomic radius / pm:114.5

Relative atomic mass:79.904 ± 0.001

 

Bromine was discovered by Antoine-Jérôme Balard (FR) in 1826. The origin of the name comes from the Greek word bromos meaning stench. It is a reddish-brown liquid with suffocating, irritating fumes that gives off poisonous vapour. It is a oxidizer that causes severe burns. Bromine occurs in compounds in sea water. It was once used in large quantities to make a compound that removed lead compound build up in engines burning leaded gasoline. Now it is primarily used in dyes, disinfectants and photographic chemicals.

Density / g dm^-3:4050 (123 K)

 3122.6 (293 K)

 7.59 (gas, 273 K)

Molar volume / cm³mol^-1:19.73 (123 K)

 25.59 (293 K)

 21055.07 (gas, 273 K)

Electrical resistivity / μΩcm:- (20 °C)

Thermal conductivity / W m^-1K^-1:0.0047

Melting point / °C:-7.2

Boiling point / °C:58.78

Heat of fusion / kJ mol^-1:10.8

Heat of vaporization / kJ mol^-1:30.5

Heat of atomization / kJ mol^-1:117.943

1st ionization energy / kJ mol^-1:1139.87

2nd ionization energy / kJ mol^-1:2103.40

3rd ionization energy / kJ mol^-1:3473.50

in the atmosphere / ppm:-

in the Earth's crust / ppm:2.5

in the oceans / ppm:65